ChangeSpec
changespec.orgOpen JSON format for API breaking changes, deprecations, and supply-chain retractions.
Dev Toolsapijson-formatbreaking-changesdeprecationsupply-chainopen-standarddeveloper-tooling
About
ChangeSpec is an open JSON event format (Apache 2.0) that standardizes how API vendors communicate breaking changes, deprecations, CVE advisories, and package retractions. It provides a single structured event schema that IDEs, CI pipelines, AI assistants, and compliance tools can consume automatically. Reference implementations are available in Go, TypeScript, and Python.
Problem
There is no standard format for API breaking change notifications, so developers miss critical changes published across disparate channels like blogs, emails, and Slack.
For
Developers consuming external APIs, API/SDK vendors, and security engineers
How it works
Vendors publish a single structured ChangeSpec JSON event per change, and any tool that supports the format automatically delivers it to developers through their preferred channel.
Business model
open-source
Status
launched
Launched
Apr 2026